For example, an apparatus for performing a process of a vapor phase growth or the like to a silicon single crystal wafer (hereinafter, referred simply as a wafer) is comprised that a wafer is transferred into a process chamber to perform a process in a state of being placed on a susceptor in the process chamber, and after the process, the wafer on the susceptor is transferred out of the process chamber.
In this case, there are various systems for placing the wafer on the susceptor or taking the wafer from the susceptor. As one of them, a system (hereinafter, referred as a lift pin system) has been well known that, for example, at least three lift pins or more provided to be capable of projection above an upper surface of a susceptor are operated to project an approximately equal length to one another, a wafer is transferred onto the lift pins which were projected to make the three or more than three lift pins support the wafer in an approximately horizontal condition, and the lift pins are gone down one another in synchronization to place the wafer onto the susceptor, meanwhile the placed wafer is gone up above the susceptor by the projection operation of the lift pins to carry the wafer out of the process chamber by a carrying apparatus (refer to Japanese Patent Application Laid Open No. 205130/1997).
However, in the lift pin system described above, when a wafer is performed mirror finished to both side surfaces of the wafer, the wafer may have a contact mark by a lift pin on a lower surface (that is, rear surface) of the wafer and appearance of the wafer becomes bad.
This invention has been accomplished for solving the aforementioned problem. An object of this invention is to provide a lift pin system of silicon single crystal wafer process apparatus capable of obtaining a silicon single crystal wafer with good appearance, a manufacturing method of a silicon epitaxial wafer, and a silicon single crystal wafer with good appearance even in the case of being attached to or detached from a susceptor in the lift pin system to perform process.